A pre-assembled electrical connection unit for a battery pack includes a bus bar defining a hole, and a cage defines a cavity. The unit also includes a fastener disposed in the cavity and the cage surrounds the fastener. The cage is secured to the bus bar, and the fastener is positioned in the hole and the cavity in an initial position. The fastener is movable to a final position relative to the cage which positions the fastener deeper in the hole of the bus bar. The unit is positioned relative to the battery pack, and the battery pack includes a module terminal. The module terminal includes a terminal nut that is accessible during an assembly process. The unit is placed over the terminal nut during the assembly process such that the fastener aligns with the terminal nut and secures the bus bar to the module terminal in the final position.